For protection against colds, pollen, house dust, PM2.5, etc. Effective cut filter Adult black mask, 100 sheets (20 sheets x 5 packs) One pack is not vacuum-sealed. Purchased at Costco several years ago. Shipped without the box, only 5 packs. BLACK MASK Quantity: 100 sheets Size: Adult size: approx. 17.5 x 9.5cm Non-woven fabric Disposable type Non-medical mask New, unused, opened item. Will be shipped after taking out of the box. Thank you for viewing.